FIG. 6 is a schematic view showing a configuration of a conventional flywheel power generating facility.
A flywheel power generator 1 includes a flywheel 1a for storing rotational energy (mechanical energy), and can convert the stored rotational energy into electric energy (electric power) to output the electric energy. For example, the flywheel power generator 1 is used to supply the electric power to a nuclear fusion test facility 6 which needs large current in a short period of time. In FIG. 6, the flywheel power generator 1 is directly connected to a driving motor 2, and the driving motor 2 is further connected to a power supply device 3. The driving motor 2 rotates the flywheel 1a, and the power supply device 3 supplies electric power to the driving motor 2.
When the flywheel power generator 1 is used as a power source of the nuclear fusion test facility 6, the flywheel power generating facility accelerates the flywheel power generator 1 by the driving motor 2 to store the rotational energy in the flywheel 1a before starting the operation of the nuclear fusion test facility 6. In this case, a detector 5 (e.g., a rotational speed detector) and a controller 4 (e.g., a rotational speed controller) are used in the flywheel power generating facility to realize stable acceleration control. For example, the detector 5 detects a rotational speed of the flywheel 1a, and the controller 4 controls the operation of the driving motor 2 based on the detected rotational speed.
While the nuclear fusion test facility 6 operates, the flywheel power generator 1 converts the stored rotational energy into the electric energy to supply the electric energy to the nuclear fusion test facility 6. As a consequence, the rotational speed of the flywheel 1a declines with reduction in rotational energy. In the flywheel power generating facility, the operation of the nuclear fusion test facility 6 is stopped when the rotational speed declines to a preset speed, and then the flywheel power generator 1 is accelerated again by the driving motor 2. In the flywheel power generating facility, the acceleration of the flywheel power generator 1 and the supply of the electric power to the nuclear fusion test facility 6 are repeated so as to operate the nuclear fusion test facility 6 repeatedly.
When the flywheel power generating facility starts up or the rotational speed of the flywheel 1a is lowered, the controller 4 controls the operation of the driving motor 2 to increase the rotational speed of the flywheel 1a up to a rated rotational speed.